Here we have yet another recently discovered mineral added to our database.
"Jinan Stone" was first collected in 2015 by Daisuke Nishio-Hamane of Tokyo University. It was referred to by this name prior to identification/classification as Jinan is the general area where the find was made.
Apparently the discovery was made on an expedition to Mount Kannan rearranged because the welfare of his colleagues' cat had prevented them visiting another area in Hiroshima Province.
Kannanite was then analysed and identified as a new mineral (IMA2015-100) by being the calcium analogue of Ardennite -(V); differing by the presence of calcium cations instead of manganse in the structure.
It is also a new member of the Ardennite Group.
Kannanite vs. Ardennite-(V)
The type locality from which it is named is Mount Kannan in Ehime Prefecture on Shikoku Island, Japan where the mineral appears to be present in deteriorating manganese ore.
So far this mineral has been typically seen as narrow closed orange veins within host rock, some with space for crystallisation.
There is a super article by Daisuke Nishio-Hamane about the discovery of kannanite and the mines/mineralogy around Jinan; written in Japanese but translates very well via Google, see link below.
It is always interesting to read about these things!